Manually operable tool for installing tubular rivets



A. E. DI MAIO MANUALLY OPERABLE TOOL FOR INSTALLING TUBULAR RIVETS wwwwa June 20, 1967 Filed Nov. 16, 1964 ATTORNEYS June 20, 1967 A- E. DI MAIO 3,326,030

MANUALLY OPERABLE TOOL FOR INSTALLING TUBULAR RIVETS Filed Nov. 16, 1964 2 Sheets$heet 2 INVENTOR. ANTHONY E. DI MAIO 'lqahu 4114.

ATTORNEYS United States Patent 3,326,030 MANUALLY OPERABLE TOOL FOR INSTALLING TUBULAR RlVETS Anthony E. Di Maio, Georgetown, Mass., assignor to Marson Fastener Corporation, Revere, Mass., a corporation of Massachusetts Fiied Nov. 16, 1964, Ser. No. 411,265 1 Claim. (Cl. 72-891) The present invention relates to fastener setting tools and, more particularly, to tools of the type adapted to set tubular rivets into an apertured structure that may be accessible from one side only. Such a tubular rivet, for example, comprises: an external tubular member of relatively ductile material having a preformed flange at the rearward end of the rivet; and an internal mandril member having a head engaging the tubular member at the forward end of the rivet and a stem projecting through the rearward end. In operation, first the forward end of the rivet is inserted through the aligned holes of a pair of work pieces to be joined with the preformed flange abut ting against the outer face of one of the workpieces. Next the stem is gripped by a tool and retracted through the rearward end in such a Way that the head deforms the tubular member at the forward end of the rivet to provide a new formed flange abutting against the outer face of the other of the workpieces. Finally continued retraction of the mandrel member, when the new formed flange sufficiently resists further endwise movement, causes a rupture within the tubular member of an expendable portion of the mandril member from the remainder, thereby leaving the rivet set into position and free of the tool. The present invention contemplates a novel manually operable rivet setting tool characterized by a reduced number of simplified parts that are capable of conveniently holding a rivet in position before setting, effectively rupturing the mandril stem with minimum ef; fort and temporarily storing the mandril stem following rupture.

The primary object of the present invention is to provide a rivet setting tool comprising a pair of handles pivoted to each other at a first center, a rocker bracket that is pivoted to one of the handles at a second center and that presents an integral jaw, and a spring biased wedging jaw that slides in the rocker bracket between a position of engagement with the integral jaw when the handles are closed and a position of disengagement with the integral jaw when the handles are opened. The arrangement is such that when the handles are opened, eccentric movement about the first and second centers causes movement of the rocker bracket and the wedging jaw toward an abutment, by which relative motion of the wedging jaw away from the stationary p-air occurs. And when the handles are closed, eccentric movement about the first and second centers causes movement of the rocker bracket and the wedging jaw away from the abutment, by which relative motion of the wedging jaw toward the stationary jaw occurs. An important feature of the arrangement is that the relative sliding motion of the wedging jaw with respect to the stationary jaw permit a mandrel stem to be retained in position with light spring bias with the handles opened both when a mandrel stem is inserted between the jaws intially and when the mandrel stem is separated from the remainder of the rivet finally.

Other objects of the present invention will in part be obvious and will in part appear hereinafter.

The invention accordingly comprises the device involving the components and relationships exemplified in the following detailed disclosure, the scope of which will be indicated in the appended claim. For a fuller understanding of the nature and objects of the present invention, reference should be had to the following detailed ice description, taken in connection With the accompanying drawings, wherein:

FIGS. 1(a) and (b) illustrate the operation of an exemplary rivet for which the rivet tool of the present invention is designed; I

FIG. 2 is a side elevation of a preferred rivet setting tool of the present invention;

FIG. 3 is a front elevation of the rivet setting tool of FIG. 1;

FIG. 4 is a broken away view of the operative components of the rivet setting tool of FIG. 1, in position at the initial stage of a rivet setting operation;

FIG. 5 is a perspective view of certain components of the rivet setting tool of FIG. 1 in exploded relation; and

FIG. 6 is a broken away view of operative components of the rivet setting tool of FIG. 1 in position at the final stage of a rivet setting operation.

Generally, as best shown in FIGS. 2 and 4, the illustrated rivet setting tool comprises: A manual control and encasing support assembly in the form of a pair of handles 2t), 22, which are pivoted about a main center 24 to each other, one of the handles providing an anvil bore 26 through which the mandril of the rivet (to be described below) may be inserted; and a mandril gripping and rupturing assembly in the form of a rocker bracket 28, which is pivoted about an eccentric center 30 at its upper extremity and provides an integral jaw 32 that is fixed with respect thereto, and a wedging jaw 34 that is slidable with respect thereto.

A typical rivet for use with the tool of the present invention is shown at 10 for use in connecting a pair of workpieces 11, 12 that are apertured at 13 by aligned holes. The rivet is shown as including a mandril 14 surrounded by a tube 15. Tube. 15 is composed of a relatively hard material such as steel. Mandril 14 is provided at one extremity with a head 16 that abuts against the forward part of tube 15 and is provided at the other extremity with a stem 17 that extends rearwardly from tube 15. Stem 17 is separated from head 16 by a constriction 18 which constitutes a weakened point at which the mandril ruptures when a predetermined tensile force is exceeded. As shown in FIG. 1(b), after tubular element 15 is inserted through aperture 13, in such a way that the flanged portion '19 of tubular element 15 abuts against the workpieces, mandril 17 when withdrawn, elfects a deformation of the head extremity of tube 15 in order to provide a flange 21 which cooperates with flange 19 in order to grip the workpieces therebetween.

As shown, handle 20 is in the form of a sheet metal fold having a pair of similarly directed channel portions 40, 42 and a reversely bent and curvilinearly shaped bite portion 44, which includes 'an extension 46 that is positioned between the forward edges of channel portions 40, 42. The side profile of handle 20 provides: A head 48 having a curved upper periphery 50 and flat lower periphery 52 from which is stamped anvil bore 26; and a reversely swept grip having a margin 54 which sweeps gradually from curve 50 and -a mar-gin 58 which breaks sharply at 56. Handle 22 provides a pair of similarly directed channel portions 60, 62 and a reversely bent bite 64. The side profile of handle 22 provides an outwardly curved section 66 which continues to a reversely curved section 68 and a conforming inside curved section corresponding in shape at 70 adjacent section 54 of handle 20. As shown, a pair of lugs one shown at 74, are stamped from handle 20 in order to limit the downward movement of handle 22 by abutting against the opposed channel sections of handle 22 when handle 22 is pivoted into its innermost position with respect to handle 20. Pivot 24 consists of a shaft 76 which projects through corresponding holes in the channel sections of handles 20, 22, being retained by a pair of opposed lock washers 78, 80.

Rocker bracket 28 is shown as including a pair of spaced channel sections 82, 84, which are integrally connected at a connecting bite constituting integral jaw 32. Theupper narrower extremities of sections 82, 84 are provided with bearing holes 86, 88. The lower, wider extremities of sections 82, 84 are provided with aligned pairs of pin holes '90, 92. Extending through and between pairs of pin holes 90, 92 are 21 pairs of pins 94, 95. Positioned between integral jaw 32 and pin holes 90, 92 inchannel sections 82, 84 are a pair of parallel slots, one of which is shown at 98. Wedging jaw 34 is positioned within and between channel sections 82, 84, being guided for sliding movement by pins 94, 96, against which the straight back profile section 100 of wedging jaw 34 abuts. A guide rod 102extends through a positioning .hole in wedging jaw 34 and oppositely through slots 98. As will be observed in FIG. 3, a shaped leaf spring 104, having opposed sections 106, 108 and hook extremities 110, 112, operates between a notch. 114 in wedging jaw 34 and pin 76 at main center 24.

In operation, normally spring 104 serves to cause stationary jaw 32 to abut against extension 46 at the head of handle 20 and to cause wedging jaw 34 to abut against profile boundary 52 in the vicinity of anvil bore 26. When a rivet mandril is inserted into position between integral jaw 32 and wedging jaw 34 it is maintained in that position by light pressure exerted by spring 104 in such a way as to prevent its dropping out of anvil bore 26. Nevertheless this tubular rivet may be manually pulled from anvil bore 26. When handles 20, 22 are manually closed into the position shown in FIG. 5, rocker bracket 28 is lifted by the eccentric action of centers 24, 30 in such a way as to cause the mandril stem to be securely gripped between integral jaw 32 and wedging jaw 34. The end result is that withdrawal of integral jaw 32 and wedging jaw 34 sets the rivet as in FIG, 1(b) with deformed portion 21 opposing flanged portion 19. When the handles are moved to their outermost position, the insertion of a new mandril stem forces the old previous mandril stem out from between the jaws for ejection from within the tool through an opening 116.

The present invention thus provides a novel rivet setting tool which conveniently, holds the mandril stem in position before, during and after setting of the rivet. Since certain changes may be made in the foregoing disclosure without departing from the scope of the invention herein, it is intended that all matter described in the foregoing specification and shown in the accompanying drawings be interpreted in an illustrative and not in a limiting sense.

What is claimed is:

A rivet setting tool for setting a rivet having an external tubular element and an internal ruptu-rable mandril element, said rivet setting tool comprising a pair of handles pivoted to each other about a main counter, a rocker bracket pivoted to one of said handles about an eccentric counter spaced from said main counter, an anvil on other of said handles providing an aperture, said rocker bracket providing an integral jaw, a wedging jaw rectilinearly slidable between positions remote from and adjacent to said integral jaw, a spring urging said wedging jaw .into the position adjacent to said integral jaw, an abutment on said other of said handles limiting movement of said wedging jaw toward said integral jaw when said handles are opened, said wedging jaw being free of said abutment when said handles are closed, said wedging jaw and said stationary jaw being operative in alignment with said aperture, said rocker bracket including parallel channel sections, a pair of stationary pins extending between the channel sections, a bite between the channel sections constituting said stationary jaw, a pair of slots in said channel sections between said bite and said stationary pins, and a movable pin affixed to said wedging jaw and extending oppositely through said slots, an edge of said wedging jaw being straight and abuting against said stationary pins, and the guidingv of said movable pin by said slots serving as constraint for said rectilinear movement.

References Cited UNITED STATES PATENTS 8/ 1962 Heidenwolf 72-391 10/1964 Elliott 72-391 CHARLES W. LANHAM, Primary Examiner. G. P. CROSBY, Assistant Examiner. 

